CVE-2026-40401

Windows TCP/IP Denial of Service Vulnerability

State: Published
Severity: 7.1 High
Published: May 12, 2026
Updated: Aug 10, 2026
Reserved: Apr 13, 2026

Description

Windows TCP/IP Denial of Service Vulnerability

Scores

CVSS	Score	Vector	Source
3.1	7.1 High	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C	microsoft

Weaknesses

CWE-476 NULL Pointer Dereference

Affected Products

Product	Versions
Windows 10 Version 1607Microsoft	10.0.14393.0 to before 10.0.14393.9140Affected
Windows 10 Version 1809Microsoft	10.0.17763.0 to before 10.0.17763.8755Affected
Windows 10 Version 21H2Microsoft	10.0.19044.0 to before 10.0.19044.7291Affected
Windows 10 Version 22H2Microsoft	10.0.19045.0 to before 10.0.19045.7417Affected
Windows 11 version 23H2Microsoft	10.0.22631.0 to before 10.0.22631.7079Affected
Windows 11 Version 23H2Microsoft	10.0.22631.0 to before 10.0.22631.7219Affected
Windows 11 Version 24H2Microsoft	10.0.26100.0 to before 10.0.26100.8457Affected
Windows 11 Version 25H2Microsoft	10.0.26200.0 to before 10.0.26200.8457Affected
Windows 11 version 26H1Microsoft	10.0.28000.0 to before 10.0.28000.2113Affected
Windows Server 2012Microsoft	6.2.9200.0 to before 6.2.9200.26079Affected
Windows Server 2012 (Server Core installation)Microsoft	6.2.9200.0 to before 6.2.9200.26079Affected
Windows Server 2012 R2Microsoft	6.3.9600.0 to before 6.3.9600.23181Affected
Windows Server 2012 R2 (Server Core installation)Microsoft	6.3.9600.0 to before 6.3.9600.23181Affected
Windows Server 2016Microsoft	10.0.14393.0 to before 10.0.14393.9140Affected
Windows Server 2016 (Server Core installation)Microsoft	10.0.14393.0 to before 10.0.14393.9140Affected
Windows Server 2019Microsoft	10.0.17763.0 to before 10.0.17763.8755Affected
Windows Server 2019 (Server Core installation)Microsoft	10.0.17763.0 to before 10.0.17763.8755Affected
Windows Server 2022Microsoft	10.0.20348.0 to before 10.0.20348.5139Affected
Windows Server 2022, 23H2 Edition (Server Core installation)Microsoft	10.0.25398.0 to before 10.0.25398.2330Affected
Windows Server 2025Microsoft	10.0.26100.0 to before 10.0.26100.32860Affected
Windows Server 2025 (Server Core installation)Microsoft	10.0.26100.0 to before 10.0.26100.32860Affected

References

Windows TCP/IP Denial of Service Vulnerabilityvendor-advisorypatch

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